Index: kdevplatform/project/abstractfilemanagerplugin.h
===================================================================
--- kdevplatform/project/abstractfilemanagerplugin.h
+++ kdevplatform/project/abstractfilemanagerplugin.h
@@ -103,6 +103,20 @@
      */
     KDirWatch* projectWatcher( IProject* project ) const;
 
+    /**
+     * @return the number of watched directories for the given @p project.
+     *
+     * Stock KDirWatch doesn't currently have a method to query the number of items it watches
+     * but it will be watching just about everything in the project so this returns the file+folder
+     * count as a reasonable approximation.
+     */
+    int watchedItems( IProject* project ) const;
+
+    /**
+     * tell the plugin that the given @p project is going to be closed.
+     */
+    void projectClosing( IProject *project );
+
 Q_SIGNALS:
     void reloadedFileItem(KDevelop::ProjectFileItem* file);
     void reloadedFolderItem(KDevelop::ProjectFolderItem* folder);
Index: kdevplatform/project/abstractfilemanagerplugin.cpp
===================================================================
--- kdevplatform/project/abstractfilemanagerplugin.cpp
+++ kdevplatform/project/abstractfilemanagerplugin.cpp
@@ -27,6 +27,9 @@
 #include <QHashIterator>
 #include <QFileInfo>
 #include <QApplication>
+#ifdef TIME_IMPORT_JOB
+#include <QElapsedTimer>
+#endif
 
 #include <KMessageBox>
 #include <KLocalizedString>
@@ -117,7 +120,18 @@
         }
         m_projectJobs.remove(project);
     }
+#ifdef TIME_IMPORT_JOB
+    QElapsedTimer timer;
+    if (m_watchers.contains(project)) {
+        timer.start();
+    }
+#endif
     delete m_watchers.take(project);
+#ifdef TIME_IMPORT_JOB
+    if (timer.isValid()) {
+        qCInfo(FILEMANAGER) << "Deleting dir watcher took" << timer.elapsed() / 1000.0 << "seconds for project" << project->name();
+    }
+#endif
     m_filters.remove(project);
 }
 
@@ -661,6 +675,16 @@
     return d->m_watchers.value( project, nullptr );
 }
 
+int AbstractFileManagerPlugin::watchedItems( IProject* project ) const
+{
+    return project->fileSet().size();
+}
+
+void AbstractFileManagerPlugin::projectClosing( IProject *project )
+{
+    d->projectClosing(project);
+}
+
 //END Plugin
 
 #include "moc_abstractfilemanagerplugin.cpp"
Index: kdevplatform/project/tests/CMakeLists.txt
===================================================================
--- kdevplatform/project/tests/CMakeLists.txt
+++ kdevplatform/project/tests/CMakeLists.txt
@@ -21,3 +21,12 @@
     KDev::Tests
     Qt5::QuickWidgets
 )
+
+add_executable(abstractfilemanagerpluginimportbenchmark
+    abstractfilemanagerpluginimportbenchmark.cpp
+)
+ecm_mark_nongui_executable(abstractfilemanagerpluginimportbenchmark)
+target_link_libraries(abstractfilemanagerpluginimportbenchmark
+    KDev::Project
+    KDev::Tests
+)
Index: kdevplatform/project/tests/abstractfilemanagerpluginimportbenchmark.cpp
===================================================================
--- /dev/null
+++ kdevplatform/project/tests/abstractfilemanagerpluginimportbenchmark.cpp
@@ -0,0 +1,164 @@
+/* This file is part of KDevelop
+    Copyright 2017 René J.V. Bertin <rjvbertin@gmail.com>
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Library General Public
+    License as published by the Free Software Foundation; either
+    version 2 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Library General Public License for more details.
+
+    You should have received a copy of the GNU Library General Public License
+    along with this library; see the file COPYING.LIB.  If not, write to
+    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+    Boston, MA 02110-1301, USA.
+*/
+
+#include <project/abstractfilemanagerplugin.h>
+#include <project/projectmodel.h>
+
+#include <tests/autotestshell.h>
+#include <tests/testcore.h>
+#include <tests/testproject.h>
+
+#include <util/path.h>
+
+#include <KJob>
+#include <KDirWatch>
+
+#include <QCoreApplication>
+#include <QList>
+#include <QFileInfo>
+#include <QElapsedTimer>
+#include <QMap>
+#include <QDebug>
+
+using namespace KDevelop;
+
+class TestFileManagerPlugin : public AbstractFileManagerPlugin
+{
+    Q_OBJECT
+public:
+    TestFileManagerPlugin(QObject* parent = nullptr)
+        : AbstractFileManagerPlugin({}, parent)
+    {}
+
+    using AbstractFileManagerPlugin::watchedItems;
+
+    using AbstractFileManagerPlugin::projectClosing;
+};
+
+class AFMPBenchmark : public QObject {
+    Q_OBJECT
+public:
+    AFMPBenchmark(TestFileManagerPlugin* manager, const QString& path, QObject* parent)
+        : QObject(parent)
+    {
+        if (QFileInfo(path).isDir()) {
+            m_manager = manager;
+            m_project = new TestProject(Path(path));
+        } else {
+            qWarning() << path << "is not a directory, ignoring";
+            m_project = nullptr;
+        }
+    }
+
+    void start()
+    {
+        if (!m_project) {
+            return;
+        }
+        m_projectNumber = s_count++;
+        qInfo() << "Starting import of project #" << m_projectNumber << "at" << m_project->path();
+        m_timer.start();
+        auto root = m_manager->import(m_project);
+        int elapsed = m_timer.elapsed();
+        qInfo() << "\tcreating dirwatcher took"
+            << elapsed / 1000.0 << "seconds";
+        auto import = m_manager->createImportJob(root);
+        QObject::connect(import, &KJob::finished, this, &AFMPBenchmark::projectImportDone);
+        m_timer.restart();
+        import->start();
+    }
+
+    void projectClosing()
+    {
+        m_timer.restart();
+        m_manager->projectClosing(m_project);
+        int elapsed = m_timer.elapsed();
+        qInfo() << "\tclosing project" << m_projectNumber << ":" << elapsed / 1000.0 << "seconds";
+    }
+
+    TestFileManagerPlugin* m_manager;
+    TestProject* m_project;
+    QElapsedTimer m_timer;
+    int m_projectNumber;
+
+    static int s_count;
+
+Q_SIGNALS:
+    void finished();
+
+private Q_SLOTS:
+    void projectImportDone(KJob* job)
+    {
+        Q_UNUSED(job);
+        int elapsed = m_timer.elapsed();
+        qInfo() << "imported project" << m_projectNumber
+            << "with" << m_project->fileSet().size()
+            << "files (watched:" << m_manager->watchedItems(m_project) << "):"
+            << elapsed / 1000.0 << "seconds";
+
+        s_count -= 1;
+        if (s_count <= 0) {
+            qInfo() << "Done.";
+            emit finished();
+        }
+    }
+
+};
+
+int AFMPBenchmark::s_count = 0;
+
+int main(int argc, char** argv)
+{
+    if (argc < 2) {
+        qWarning() << "Usage:" << argv[0] << "projectDir1 [...projectDirN]";
+        return 1;
+    }
+    QCoreApplication app(argc, argv);
+
+    AutoTestShell::init();
+    auto core = TestCore::initialize(Core::NoUi);
+    auto manager = new TestFileManagerPlugin(core);
+
+    const char *kdwMethod[] = {"FAM", "Inotify", "Stat", "QFSWatch"};
+    qInfo() << "KDirWatch backend:" << kdwMethod[KDirWatch().internalMethod()];
+
+    QList<AFMPBenchmark*> benchmarks;
+
+    for (int i = 1 ; i < argc ; ++i) {
+        const auto benchmark = new AFMPBenchmark(manager, QString::fromUtf8(argv[i]), core);
+        benchmarks << benchmark;
+        QObject::connect(benchmark, &AFMPBenchmark::finished,
+                     &app, [&benchmarks] {
+                        for (auto benchmark : benchmarks) {
+                            benchmark->projectClosing();
+                        }
+                        QCoreApplication::instance()->quit();
+                     });
+    }
+    for (auto benchmark : benchmarks) {
+        benchmark->start();
+    }
+
+    if (benchmarks.first()->s_count > 0) {
+        return app.exec();
+    }
+    return 1;
+}
+
+#include "abstractfilemanagerpluginimportbenchmark.moc"